1. Field of the Invention
The present invention relates to a power unit attached to a transmission actuating device, a power unit attached to a clutch actuating device, or a power unit attached to both a transmission actuating device and a clutch actuating device, mounted on a vehicle such as a motorcycle.
2. Description of Related Art
A power unit for a vehicle having a crankshaft oriented in the longitudinal direction of the vehicle and having an internal combustion engine is disclosed in Japanese Patent Publication Laid-open No. Sho. 37-16106.
With such a vehicle power unit, a drive motor section for performing transmission actuation is provided inside the power unit, which means that it is difficult to carry out maintenance and it is difficult to adjust the drive motor section.
Also, since the drive motor section is provided linked to the transmission, a casing housing the drive motor section and the transmission is enlarged, and it is difficult to increase the space for an operator""s legs.
The present invention relates to improvements to a power unit for a vehicle that solves these type of problems, and provides a power unit for a vehicle having an internal combustion engine mounted so that a crank shaft is oriented in the longitudinal direction of the vehicle body, and having a transmission arranged behind the internal combustion engine, wherein one or both of a transmission actuating electric motor for driving a transmission actuating device of the transmission and a clutch actuating electric motor for driving a clutch actuating device of a clutch are arranged in a rear section of the power unit.
In the present invention, since the electric motors are arranged in a rear portion of the power unit, maintenance and adjustment of the electric motors can be simply and easily carried out even in a case where the power unit is not disassembled. Also, operators comfort when riding can be improved by widening a space for an operator""s legs.
Further, with the structure of the present invention, it is possible to effectively utilize a space between pivot portions of a pair of left and right rear forks, and it is possible to reliably protect the electric motors by means of the pivot portions of the rear forks.
Still further, with the structure of the present invention, the manufacture of rotary shafts of the electric motors and shafts coupled to these rotary shafts is carried out at the same time as the manufacture of rotary shafts of the transmission and clutch, and it is possible to improve productivity.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.